Intelligence - Bell Curve - Herrnstein And Murray

This post will largely consist of quotes from the Bell Curve book (with no permission). 

1. "[Spearman] hypothesized that g is a general capacity for inferring and applying relationships drawn from experience. Being able to grasp, for example, the relationship between a pair of words like harvest and yield, or to recite a list of digits in reverse order, or to see what a geometrical pattern would look like upside down, are examples of tasks (and of test items) that draw on g as Spearman conceived of it. This definition of intelligence differed subtly from the more prevalent idea that intelligence is the ability to learn and to generalize what is learned. The course of learning is affected by intelligence, in Spearman's view, but it was not the thing in itself. Spearmanian intelligence was a measure of a person's capacity for complex mental work."
2. "In a lengthy exchange in the New Republic in 1922 and 1923 with Lewis Terman, premieAr merican tester of the time and the developer of the Stanford-Binet IQ test, Lippmann wrote, "I hate the impudence of a claim that in fifty minutes you can judge and classify a human being's predestined fitness in life. I hate the pretentiousness of that claim. I hate the abuse of scientific method which it involves. I hate the sense of superiority which it creates, and the sense of  inferiority which it imposes." - so F and so anti NT (as in MBTI)."
3. "To those who held the behaviorist view, human potential was almost perfectly malleable, shaped by the environment. The causes of human deficiencies in intelligence--or parenting, or social behavior, or work behavior-lay outside the individual. They were caused by flaws in society. Sometimes capitalism was blamed, sometimes an uncaring or incompetent incompetent government. Further, the causes of these deficiencies could be fixed by the right public policies-redistribution of wealth, better education, better housing and medical care. Once these environmental causes were removed, the deficiencies should vanish as well, it was argued. The contrary notion-that individual differences could not easily be diminished by government intervention-collided head-on with the enthusiasm for egalitarianism, which itself collided head-on with a half century of IQ data indicating that differences in intelligence are intractable and significantly heritable and that the average IQ of various socioeconomic and ethnic groups differs."
4. "Given two 11 year olds, one with an IQ of 110 and one with an IQ of 90, what can you tell us about the differences between those two children?" The answer must be phrased very tentatively. On many important topics, the answer must be, "We can tell you nothing with any confidence," It is well worth a guidance counselor's time to know what these individual scores are, but only in combination with a variety of other information about the child's personality, talents, and background. The individual's IQ score all by itself is a useful tool but a limited one. Suppose instead that the question at issue is: "Given two sixth-grade classes, one for which the average IQ is 110 and the other for which it is 90, what can you tell us about the difference between those two classes and their average prospects for the future!" Now there is a great deal to be said, and it can be said with considerable confidence-not about any one person in either class but about average outcomes that are important to the school, educational policy in general, and society writ large."
5. "Or a plumber with a measured IQ of 100--only an average IQ--can know a great deal about the functioning of plumbing systems. He may be able to diagnose problems, discuss them artic~~latelmy,a ke shrewd decisions about how to fix them, and, while he is working, make some pithy remarks about the president's recent speech. - IQ should not be identified with other good qualities like humor."
6. "Many witty people do not have unusually high test scores, hut someone who regularly tosses off impromptu complex puns probably does (which does nor necessarily mean that such puns are very funny, we hasten to add)."
7. "To say that most of the people in the cognitively demanding positions of a society have a high IQ is not the same as saying that most of the people with high IQs are in such position. A large majority of the smart people in Cheap's Egypt, dynastic China, Elizabethan England, and Teddy Roosevelt's America were engaged in ordinary pursuits, mingling, working, and living with everyone else. Many were housewives. Most of the rest were farmers, smiths, millers, bakers, carpenters, and shopkeepers. Social and economic stratification was extreme, but cognitive stratification was minor."
8. "Relatives occupy neighboring, if not the same, rungs on the job status ladder, and the closer the relationship is, the nearer they are. Such commonplace findings have many possible explanations, but an obvious one that is not mentioned or tested often by social scientists is that since intelligence runs in families and intelligence predicts status, status must run in families. In fact, this explanation somehow manages to be both obvious and controversial."
9. "An IQ score is a better predictor of job productivity than a job interview, reference checks, or college transcript." - Is this really true? I guess the authors' perspective applies to a group rather than to a specific person.
10. "Most sweepingly important, an employer that is free to pick among applicants can realize large economic gains from hiring those with the highest 1Qs. An economy that let employers pick applicants with the highest lQs is a significantly more efficient economy. Herein lies the policy problem: Since 1971, Congress and the Supreme Court have effectively forbidden American employers from hiring based on intelligence tests." - extrapolating this if we "hired" fathers, wives, husbands, uncles etc based on IQ instead of on other factors would we be better off? 
11. The third possibility is that cognitive ability itself-sheer intellectual horsepower, independent of education-has market value, Seen from this perspective, the college degree is not a credential but an indirect measure of intelligence. People with college degrees tend to be smarter than people without them and, by extension, more valuable in the marketplace. Employers recruit at Stanford or Yale not because graduates of those schools know more than graduates of less prestigious schools but for the same generic reason that Willie Sutton gave for robbing banks. Places like Stanford and Yale are where you find the coin of cognitive talent. 
12. The most comprehensive modem surveys of the use of tests for hiring, promotion, and licensing, in civilian, military, private, and government occupations, repeatedly point to three conclusions about worker performance as follows - the first of which is: Job training and job performance in many common occupations are well predicted by any broadly based test of intelligence, as compared to narrower tests more specifically targeted to the routines of the job. As a corollary: Narrower tests that predict well do so largely because they happen themselves to be correlated with tests of general cognitive ability.
13. I am not able to get the exact quote but the performance of students apparently improved by about 3% points where the teacher's IQ was higher (by how much?). - Now if the performance and success of people is largely related to their IQ, how can any teacher make any difference?
14. "Surprising as it may seem, the predictive power of tests for job performance lies almost completely in their ability to measure the most general form of cognitive ability, g, and has little to do with their ability to measure aptitude or knowledge for a particular job."
16. "At a run-of-the mill family restaurant, what distinguishes a really good busboy from an average one? Being a busboy is a straightforward job. The waiter takes the orders, deals with the kitchen, and serves the food while the busboy totes the dirty dishes out to the kitchen, keeps the water glasses filled, and helps the waiter serve or clear as required. In such a job, a high IQ is not required. One may be a good busboy simply with diligence and good spirits. But complications arise. A busboy usually works with more than one waiter. The restaurant gets crowded. A dozen things are happening at once. The busboy is suddenly faced with queuing problems, with setting priorities. A really good busboy gets the key station cleared in the nick of time, remembering that a table of new orders near that particular station is going to be coming out of the kitchen; when he goes to the kitchen, he gets a fresh water pitcher and a fresh condiment tray to save an extra trip. He knows which waiters appreciate extra help and when they need it. The point is one that should draw broad agreement from readers who have held menial jobs: Given the other necessary qualities of diligence and good spirits, intelligence helps. The really good busboy is engaged in using g when he is solving the problems of his job, and the more g he has, the more quickly he comes up with the solution."
17. "How good a predictor of job productivity is a cognitive test score compared to a job interview? Reference checks! College transcript? The answer, probably surprising to many, is that the test score is a better predictor of job performance than any other single measure."
18. "Think now of a particular worker-a secretary, let us say. You have a choice between hiring an average secretary, who by definition is at the 50th percentile, or a first-rate one-at the 84th percentile, let us say. If you were free to set their salaries at the figures you believe to reflect their true worth, how different would they be? We imagine that anyone who has worked with average secretaries and first-rate ones will answer "a lot." The consensus among experts has been that, measured in dollars, "a lot" works out, on the average, to about a 40 percent premium. Put more technically and precisely, one standard deviation of the distribution of workers' annual productivities in a typical occupation is worth 40 percent of the average worker's annual income.[43N1 ew work suggests the premium may actually be twice as large. Since the larger estimate has yet to be confirmed, we will base our calculations on the more conservative estimate." To take a specific example, for a $20,000-a-year job, which is correctly priced for an average worker, the incremental value of hiring a new worker who is one standard deviation above the mean-at the 84th percentile-is $8,000 per year."
19. "Getting high quality for a complex job can be worth large multiples of what it is worth to get equally high quality for a simpler job."
20. "The question arises whether the employer gains much by a rigorous selection process for choosing among the people who actually do show up at the job interview. Aren't they already so highly screened that they are, in effect, homogeneous? The answer is intimately related to the size of the stakes. When the job is in a top Wall Street firm, for example, the dollar value of output is so high that the difference between a new hiree who is two standard deviations above the mean and one who is four standard deviations above the mean on any given predictor measure can mean a huge economic difference, even though the "inferior" applicant is already far into the top few centiles in ability." - Should professional footballers and basketball (and cricket) players be recruited on the basis of their g or IQ? Doesn't seem to make sense.
21. "A case study of what happens when a public service is able to hire from the top down on a test of cognitive ability, drawing on a large applicant pool, comes out of New York City. In April 1939, after a decade of economic depression, New York City attracted almost 30,000 men to a written and physical examination for 300 openings in the city's police force, a selection ratio of approximately one in a hundred.57 The written test was similar to the intelligence test then being given by the federal civil service. Positions were offered top down for a composite score on the mental and physical tests, with the mental test more heavily weighted by more than two to one. Not everyone accepted the offer, but, times being what they were, the 300 slots were filled by men who earned the top 350 scores. Inasmuch as the performance of police officers has been shown to correlate significantly with scores on intelligence tests,5Rt his group of men should have made outstanding policemen. And they did, achieving extraordinarily successful careers in and out of policing. They attained far higher than average rank as police officers. Of the entire group, four have been police chiefs, four deputy commissioners, two chiefs of personnel, one a chief inspector, and one became commissioner of the New York Police Department. They suffered far fewer disciplinary penalties, and they contributed significantly to the study and teaching of policing and law enforcement. Many also had successful careers as lawyers, businessmen, and academics after leaving the police department."
22. "We leave the analysis of labor force participation with a strong case to be made for two points: Cognitive ability is a significant determinant of dropout from the labor force by healthy young men, independent of other plausibly important variables. And the group of men who are our of the labor force because of self-described physical disability tend toward low cognitive ability, independent of the physical demands of their work."
23. "High IQ lowers the probability of a month-long spell of unemployment among white men, while socioeconomic background has no effect...The most basic implication of the analysis is that intelligence and its correlates-maturity, farsightedness, and personal competence-are important in keeping a person employed and in the work force...Condescension toward these men is not in order, nor are glib assumptions that those who are cognitively disadvantaged cannot be productive citizens. The world is statistically tougher for them than for others who are more fortunate, but most of them are overcoming the odds."
24. "For marriage, the general rule is that the more intelligent get married at higher rates than the less intelligent. This relationship, which applies across the range of intelligence, is obscured among people with high levels of education because college and graduate school are powerful delayers of marriage. Even among young women who have grown up in broken homes and among young women who are poor - both of which foster illegitimacy - low cognitive ability further raises the odds of giving birth illegitimately. Low cognitive ability is a much stronger predisposing factor for illegitimacy than low socio economic background." If this is true why have the authors mentioned "both of which foster illegitimacy" leaving the word "supposedly" out?
25. "Higher divorce rate is associated with lower IQ and with higher SES (socio economic status) of parents - meaning that if your parents had a higher SES then you are more likely to get divorced. Same if your IQ was lower."
26. "In his research early in the century, Malinowski observed a constant running throughout the rich diversity of human cultures and indeed throughout history. He decided that this amounted to "a universal sociological law" and called it the "principle of legitimacy." No matter what the culture might be, "there runs the rule that the father is indispensable for the full sociological status of the child as well as of the mother, that the group consisting of a woman and her offspring is sociologically incomplete and illegitimate."" The rule applied alike to East or West, primitive cultures or advanced ones, cultures where premarital sex was accepted or banned, where children were considered an asset or a burden, where fathers could have one wife or many." - This is very interesting that even the father is indispensable for the full status of the mother also. I wonder how this is proved or explained.
27. "Thus the illegitimacy ratio increased by sixfold from 1960 to 1990-bad enough-but the number of never married mothers increased forty fold." I wonder what the authors mean by this and the implication thereof. That many never married mother gave birth to non-illegitimate children? 
28. "How intelligent a woman is may interact with her impulsiveness, and hence her ability to exert self-discipline and restraint on her partner in order to avoid pregnancy." - meaning intelligence and impulsiveness (usually) cannot coexist? Whoa... Again looking at it from another angle - the authors are making the same assumption or mistake that I frequently make - assuming that NT and J (as in MBTI) are synonymous. And P (impulsiveness) hence correlates with SF and hence indicates low IQ.
29. "The proportions of illegitimate first births in the top two cognitive classes are nearly the same, rounding to 7 percent-about half the proportion for Class 111, a third of the proportion for Class IV, and a sixth of the proportion for Class V. Illegitimacy is again conspicuously concentrated in the lowest cognitive groups. Not only are children of mothers in the top quartile of intelligence (Classes I and 11) more likely to he born within marriage, they are more likely to have been conceived within marriage (no shotgun wedding)." Note that highest IQ is Class I and lowest in Class V.
30. "We have already noted that family structure at the age of 14 had only modest influence on the chances of getting divorced in the NLSY sample after controlling for IQ and parental SES. Now the question is how the same characteristic affects illegitimacy. Let us consider a white woman of average intelligence and average socioeconomic background. The odds that her first child would be born out of wedlock were: 
    1. 10 percent if she was living with both biological parents.
    2. 18 percent if she was living with a biological parent and a stepparent.
    3. 25 percent if she was living with her mother (with or without a livein boyfriend)."
31. "High socioeconomic status offered weak protection against illegitimacy once IQ had been taken into account."
32. "The welfare check (and the collateral goods and services that are part of the welfare system) enabks women to do something that many young women might naturally like to do anyway: bear children. For affluent young women, the welfare system is obviously irrelevant. They are restrained from having babies out of wedlock by moral considerations or by fear of the social penalties (both of which still exist, though weakened, in middle-class circles), by a concern that the child have a father around the house, and because having a baby would interfere with their plans for the future. In the poorest communities, having a baby out of wedlock is no longer subject to social stigma, nor do moral considerations appear to carry much weight any longer; it is not irresponsible to have a child out of wedlock, the argument is more likely to go, because a single young woman can in fact support the child without the help of a husband." And that brings the welfare system into the picture. For poor young women, the welfare system is highly relevant, easing the short-term economic penalties that might ordinarily restrain their childbearing. The poorer she is, the more attractive the welfare package is and the more likely that she will think herself enabled to have a baby by receiving it."
33. "It is one thing to say that single women with babies are disproportionately poor. That makes sense, because a single woman with a child is often not a viable economic unit. It is quite another thing to say that women who are already poor become mothers. Now we are arguing that there is something about being in the state of poverty itself (after holding the socioeconomic status in which they were raised constant) that makes having a baby without a husband attractive."
34. "Among NLSY white mothers who were below the poverty line in the year prior to giving birth, what proportion of the babies were born out of wedlock? The answer is 44 percent. Among NLSY white mothers who were anywhere above the poverty line in the year before giving birth, what proportion of the babies were born out of wedlock? The answer is only 6 percent. It is a huge difference and makes a prima facie case for those who argue that poverty itself, presumably via the welfare system, is an important cause of illegitimacy."
35. "For example, many people have argued that the welfare system cannot really be a cause of illegitimacy, because, in objective terms, the welfare system is a bad deal. It provides only enough to squeak by, it can easily trap young women into long-term dependence, and even poor young women would be much better off by completing their education and getting a job rather than having a baby and going on welfare. The results we have presented can be  interpreted as saying that the welfare system may he a had deal, but it takes foresight and intelligence to understand why. For women without foresight and intelligence, it may seem to be a good deal. Hence poor young women who are bright tend not to have illegitimate babies nearly as often as poor young women who are dull. Another possibility fits in with those who argue that the best preventative for illegitimacy is better opportunities. It is not the welfare system that is at fault but the lack of other avenues. Poor young women who are bright are getting scholarships, or otherwise having positive incentives offered to them, and they accordingly defer childbearing. Poor young women who are dull do not get such opportunities; they have nothing else to do, and so have a baby. The goal should he to provide them too with other ways of seeing their futures."
36. "The percentage of households with children that consist of a married couple: 87 percent in the top quartile of IQ, 70 percent in the bottom quartile. The percentage of households with children that have experienced divorce: 17 percent in the top quartile of IQ, 33 percent in the bottom quartile. The percentage of children born out of wedlock: 5 percent in the top quartile of IQ, 23 percent in the bottom quartile. The American family may be generally under siege, as people often say. Rut it is at the bottom of the cognitive ability distribution that its defenses are most visibly crumbling."

Review of this book is here and here. Quote from the second link:

•  "Take a trait that is far more heritable than anyone has ever claimed IQ to be but is politically uncontroversial—body height. Suppose that I measured the heights of adult males in a poor Indian village beset with nutritional deprivation, and suppose the average height of adult males is five feet six inches. Heritability within the village is high, which is to say that tall fathers (they may average five feet eight inches) tend to have tall sons, while short fathers (five feet four inches on average) tend to have short sons. But this high heritability within the village does not mean that better nutrition might not raise average height to five feet ten inches in a few generations. Similarly, the well–documented fifteen–point average difference in IQ between blacks and whites in America, with substantial heritability of IQ in family lines within each group, permits no automatic conclusion that truly equal opportunity might not raise the black average enough to equal or surpass the white mean."

Quote from the 1st review link:

• "One of The Bell Curve's theoretical linchpins is the high heritability of IQ. Herrnstein and Murray, sounding like the souls of caution, write that 'half a century of work, now amounting to hundreds of empirical and theoretical studies, permits a broad conclusion that the genetic component of IQ is unlikely to be smaller than 40 per cent or higher than 80 per cent. ... For purposes of this discussion, we will adopt a middling estimate of 60 per cent heritability.' This now looks seriously overstated. Michael Daniels, Bernie Devlin, and Kathryn Roeder of Carnegie Mellon University took the same studies on which Herrnstein and Murray based their estimate, and subjected them to a computer meta-analysis ('a powerful method of statistical analysis'--The Bell Curve). Their paper, which has not yet been published, says: "In brief, studies of IQ, and our reanalyses of them, suggest a narrow-sense heritability of 34 per cent and a broad-sense heritability of 46 per cent. [The difference between broad and narrow is too technical to explain in this limited space.] This is a far cry from Herrnstein and Murray's maximum value of 80 per cent or their middling value of 60 per cent. Consequently, Herrnstein and Murray give the impression that IQ is highly 'heritable,' but it is not."
• "As an example of where the kind of analysis Herrnstein and Murray didn't do can lead, a new study by Jay Girotto and Paul Peterson of Harvard shows that students who raise their grades and take harder courses can increase their IQ scores by an average of eight points during the first three years of high school." - whoa. WOWOWOW. Is this true? Can it happen?